Report on Awu (Indonesia) — 8 December-14 December 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
8 December-14 December 2021
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2021. Report on Awu (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 8 December-14 December 2021. Smithsonian Institution and US Geological Survey.
3.689°N, 125.447°E; summit elev. 1318 m
All times are local (unless otherwise noted)
PVMBG reported that volcanic seismicity at Awu had increased beginning in October. Notably, the number of shallow volcanic earthquakes increased to 7-26 events per day from the previous maximum of 5 daily events. The number of deep volcanic earthquakes also increased. The Alert Level was raised to 2 (on a scale of 1-4) and the public was warned to stay 1 km away from the summit crater. The report also noted that no emissions nor any other surficial activity had been visible during 1 September-10 December, though weather sometimes hindered views.
Geological Summary. The massive Gunung Awu stratovolcano occupies the northern end of Great Sangihe Island, the largest of the Sangihe arc. Deep valleys that form passageways for lahars dissect the flanks of the volcano, which was constructed within a 4.5-km-wide caldera. Powerful explosive eruptions in 1711, 1812, 1856, 1892, and 1966 produced devastating pyroclastic flows and lahars that caused more than 8000 cumulative fatalities. Awu contained a summit crater lake that was 1 km wide and 172 m deep in 1922, but was largely ejected during the 1966 eruption.